"""
DocMind - Multi-Agent System
Implements Retriever, Reader, Critic, and Synthesizer agents
"""

from typing import List, Dict, Tuple
from retriever import PaperRetriever
import os


class RetrieverAgent:
    """Agent responsible for finding relevant papers"""

    def __init__(self, retriever: PaperRetriever):
        self.retriever = retriever

    def retrieve(self, query: str, top_k: int = 5) -> List[Tuple[Dict, float]]:
        """
        Retrieve relevant papers for the query

        Returns:
            List of (paper, relevance_score) tuples
        """
        print(f"🔍 Retriever Agent: Searching for '{query}'...")
        results = self.retriever.search(query, top_k)
        print(f"   Found {len(results)} relevant papers")
        return results


class ReaderAgent:
    """Agent responsible for reading and summarizing papers"""

    def __init__(self, llm_client=None):
        """
        Args:
            llm_client: Optional LLM client (OpenAI, Anthropic, etc.)
                       If None, uses rule-based summarization
        """
        self.llm_client = llm_client

    def summarize_paper(self, paper: Dict) -> str:
        """
        Generate a summary of a single paper

        Args:
            paper: Paper dictionary with title, abstract, etc.

        Returns:
            Summary string
        """
        if self.llm_client:
            return self._llm_summarize(paper)
        else:
            return self._rule_based_summarize(paper)

    def _rule_based_summarize(self, paper: Dict) -> str:
        """Simple extractive summary (first 3 sentences)"""
        abstract = paper['abstract']
        sentences = abstract.split('. ')
        summary = '. '.join(sentences[:3]) + '.'

        return {
            'title': paper['title'],
            'arxiv_id': paper['arxiv_id'],
            'authors': paper['authors'][:3],
            'summary': summary,
            'year': paper['published'][:4]
        }

    def _llm_summarize(self, paper: Dict) -> str:
        """Use LLM to generate intelligent summary"""
        prompt = f"""Summarize this research paper in 2-3 sentences, focusing on:
1. The main contribution/idea
2. The key methodology or approach
3. Important results or implications

Title: {paper['title']}
Abstract: {paper['abstract']}

Summary:"""

        # Call LLM (implementation depends on client)
        # This is a placeholder - replace with actual LLM call
        response = "LLM summary would go here"

        return {
            'title': paper['title'],
            'arxiv_id': paper['arxiv_id'],
            'authors': paper['authors'][:3],
            'summary': response,
            'year': paper['published'][:4]
        }

    def read_papers(self, papers: List[Tuple[Dict, float]]) -> List[Dict]:
        """
        Read and summarize multiple papers

        Args:
            papers: List of (paper, score) tuples from retriever

        Returns:
            List of summaries
        """
        print(f"📖 Reader Agent: Reading {len(papers)} papers...")
        summaries = []

        for paper, score in papers:
            summary = self.summarize_paper(paper)
            summary['relevance_score'] = score
            summaries.append(summary)

        print(f"   Generated {len(summaries)} summaries")
        return summaries


class CriticAgent:
    """Agent responsible for evaluating and filtering summaries"""

    def __init__(self, llm_client=None):
        self.llm_client = llm_client

    def critique(self, summaries: List[Dict], query: str) -> List[Dict]:
        """
        Evaluate summaries for quality and relevance

        Args:
            summaries: List of paper summaries
            query: Original user query

        Returns:
            Filtered and scored summaries
        """
        print(f"🔎 Critic Agent: Evaluating {len(summaries)} summaries...")

        # Simple rule-based filtering
        filtered = []
        for summary in summaries:
            # Check relevance score threshold
            if summary['relevance_score'] > 0.3:
                # Add quality score (can be enhanced with LLM)
                summary['quality_score'] = self._assess_quality(summary, query)
                filtered.append(summary)

        # Sort by combined score
        filtered.sort(
            key=lambda x: x['relevance_score'] * 0.7 + x['quality_score'] * 0.3,
            reverse=True
        )

        print(f"   Retained {len(filtered)} high-quality summaries")
        return filtered

    def _assess_quality(self, summary: Dict, query: str) -> float:
        """
        Simple quality assessment (can be enhanced with LLM)

        Returns:
            Quality score 0-1
        """
        score = 0.5  # Base score

        # Longer summaries might be more informative
        if len(summary['summary']) > 100:
            score += 0.2

        # Recent papers get bonus
        if int(summary['year']) >= 2024:
            score += 0.3

        return min(score, 1.0)


class SynthesizerAgent:
    """Agent responsible for synthesizing final answer"""

    def __init__(self, llm_client=None):
        self.llm_client = llm_client

    def synthesize(
            self,
            summaries: List[Dict],
            query: str,
            max_papers: int = 10
    ) -> str:
        """
        Synthesize final answer from summaries

        Args:
            summaries: List of filtered, quality summaries
            query: Original user query
            max_papers: Maximum papers to include in response

        Returns:
            Final synthesized response with citations
        """
        print(f"✨ Synthesizer Agent: Creating final response...")

        if not summaries:
            return "No relevant papers found for your query."

        # Limit to top papers
        top_summaries = summaries[:max_papers]

        if self.llm_client:
            return self._llm_synthesize(top_summaries, query)
        else:
            return self._rule_based_synthesize(top_summaries, query)

    def _rule_based_synthesize(self, summaries: List[Dict], query: str) -> str:
        """Create structured response without LLM"""
        response = f"# Research Summary: {query}\n\n"
        response += f"Based on {len(summaries)} relevant papers from arXiv:\n\n"

        for i, summary in enumerate(summaries, 1):
            response += f"## [{i}] {summary['title']}\n"
            response += f"**Authors:** {', '.join(summary['authors'])}"
            if len(summary['authors']) >= 3:
                response += " et al."
            response += f"\n**Year:** {summary['year']}\n"
            response += f"**arXiv ID:** {summary['arxiv_id']}\n"
            response += f"**Relevance:** {summary['relevance_score']:.2f}\n\n"
            response += f"{summary['summary']}\n\n"
            response += "---\n\n"

        return response

    def _llm_synthesize(self, summaries: List[Dict], query: str) -> str:
        """Use LLM to create coherent synthesis"""
        # Build context from summaries
        context = ""
        for i, summary in enumerate(summaries, 1):
            context += f"[{i}] {summary['title']} ({summary['arxiv_id']})\n"
            context += f"    {summary['summary']}\n\n"

        prompt = f"""You are a research assistant. Based on the following papers, answer this question:

Question: {query}

Papers:
{context}

Provide a comprehensive answer that:
1. Directly addresses the question
2. Synthesizes information across papers
3. Cites papers by number [1], [2], etc.
4. Highlights key findings and consensus/disagreements
5. Is concise but thorough (3-5 paragraphs)

Answer:"""

        # Placeholder for LLM call
        response = "LLM-generated synthesis would go here with citations"

        # Append paper references
        response += "\n\n## References\n"
        for i, summary in enumerate(summaries, 1):
            response += f"[{i}] {summary['title']} "
            response += f"({summary['arxiv_id']}, {summary['year']})\n"

        return response


class DocMindOrchestrator:
    """Main orchestrator that coordinates all agents"""

    def __init__(
            self,
            retriever: PaperRetriever,
            llm_client=None
    ):
        self.retriever_agent = RetrieverAgent(retriever)
        self.reader_agent = ReaderAgent(llm_client)
        self.critic_agent = CriticAgent(llm_client)
        self.synthesizer_agent = SynthesizerAgent(llm_client)

    def process_query(
            self,
            query: str,
            top_k: int = 10,
            max_papers_in_response: int = 5
    ) -> str:
        """
        Process user query through full agent pipeline

        Args:
            query: User question
            top_k: Number of papers to retrieve
            max_papers_in_response: Max papers in final response

        Returns:
            Final synthesized answer
        """
        print(f"\n{'=' * 60}")
        print(f"Processing query: {query}")
        print('=' * 60)

        # Step 1: Retrieve
        papers = self.retriever_agent.retrieve(query, top_k)

        if not papers:
            return "No relevant papers found for your query."

        # Step 2: Read & Summarize
        summaries = self.reader_agent.read_papers(papers)

        # Step 3: Critique & Filter
        quality_summaries = self.critic_agent.critique(summaries, query)

        # Step 4: Synthesize
        final_response = self.synthesizer_agent.synthesize(
            quality_summaries,
            query,
            max_papers_in_response
        )

        print(f"{'=' * 60}\n")
        return final_response


def main():
    """Example usage of multi-agent system"""
    from fetch_arxiv_data import ArxivFetcher

    # Setup
    fetcher = ArxivFetcher()
    retriever = PaperRetriever()

    # Load or build index
    if not retriever.load_index():
        papers = fetcher.load_papers("arxiv_papers.json")
        retriever.build_index(papers)
        retriever.save_index()

    # Create orchestrator
    orchestrator = DocMindOrchestrator(retriever)

    # Test queries
    test_queries = [
        "What are the latest improvements in diffusion models?",
        "How does RLHF compare to DPO for language model alignment?",
        "What are the main challenges in scaling transformers?"
    ]

    for query in test_queries:
        response = orchestrator.process_query(query, top_k=8, max_papers_in_response=3)
        print(response)
        print("\n" + "=" * 80 + "\n")


if __name__ == "__main__":
    main()